President Obama said a constitutional amendment should be considered to undo the 2010 Supreme Court ruling in Citizens United that paved the way for a flood of campaign cash from corporations and wealthy special interests. Obama made the comment Wednesday in an online chat with the website Reddit. "I applaud President Obama for expressing support for a serious effort to restore the democratic foundations of our country that are under severe attack as a result of the disastrous Supreme Court ruling in Citizens United," Sen. Bernie Sanders said on Thursday.